This invention relates to an induction system for an internal combustion engine and more particularly an improved induction system for the powering internal combustion engine of a snowmobile.
It is the normal practice in snowmobiles to position the powering internal combustion engine within an engine compartment. This is done to protect the engine from the surrounding environment and also to insure that the engine can operate at the desired temperature. However, by so enclosing the engine certain components of the engine which may require frequent servicing also become enclosed.
For example, it is the normal practice to employ an induction system for the engine that incorporates a filter element for precluding foreign material from entering into the engine through its induction system. However, if the induction system and filter element is positioned within the engine compartment, then it is difficult if not impossible for the operator to readily determine if the filter element has been clogged. Clogging of filter elements is a common problem with snowmobiles due to the fact that they operate in an atmosphere wherein fine snow particles are always swirling around the engine. These snow particles can imbed themselves in the inlet side of the filter element and if this is not seen by the operator, then the engine efficiency can seriously deteriorate.
It is, therefore, a principal object of this invention to provide an induction system for the engine of a snowmobile wherein the condition of the filter element may be readily viewed by the operator.
It is a further object of this invention to provide an improved filtering arrangement for the induction system of a snowmobile engine.
In connection with the induction system for a snowmobile engine, it is desirable to insure that the engine can induct air that is not at an elevated temperature. However, it is also desirable to insure that the temperature of the air inducted into the engine remains fairly constant through out the running conditions. If the temperature of the inducted air varies, then the fuel air ratio can vary in relation to the air temperature and result in uneven performance. This becomes a problem if all of the induction air for the engine is drawn from the atmosphere and is not preheated.
It is, therefore, a still further object of this invention to provide an induction system for an internal combustion engine powering a snowmobile wherein the temperature of the inducted air is maintained more uniform regardless of ambient conditions.